1. Field of the Invention
The present invention relates to vehicle tiredness alleviating system, more particularly relates to a vehicle tiredness alleviating system which judges the tiredness of a driver and controls the air-conditioning, adjusts the temperature of the seat, or causes the seat to vibrate in accordance with the judged tiredness.
2. Description of the Related Art
In the past, it has been proposed to adjust the temperature of a vehicle seat using a seat heater, seat air-conditioner, etc. In the case of a seat heater, for example an electric heater buried inside the seat is used to warm the seat to a temperature set by the driver. A seat air-conditioner uses a device for heating and cooling air to blow warm air or cool air from a plurality of air vents provided at the seat and thereby bring the seat temperature near the temperature setting.
Further, in vehicle seats etc., it has been proposed to build in a vibration unit causing vibration inside a seat and use this to make the seat vibrate so as to give vibration to a seated person to reduce tiredness or suppress an increase in tiredness. If giving vibration to a seated person, the muscles and veins relax and circulation is promoted, whereby removal of fatigue substances is promoted and thereby tiredness is reduced or the increase in tiredness is suppressed.
Further, as a vehicle air-conditioning system, a vehicle air-conditioning system provided with an air-conditioning system unit, a pressure sensor provided at the driver's seat for detecting a pulse wave of the driver, and a tiredness judging means for estimating (judging) the tiredness of the driver based on a detection signal from the pressure sensor and outputting a command signal based on the judged tiredness to the air-conditioning system unit has been proposed.
In the above related art, however, even when a person sitting on a seat becomes tired, the seat temperature is controlled to approach the temperature setting, so in the state where the seat temperature is higher compared with the temperature setting, even when the seated person is tired, the seat will be cooled or the heating of the seat will be stopped, so the back, lumbar, calves, and other parts of the body contacting the seat will be cooled and the flow of blood will become poor. If continuing to sit in this state for a long time, the veins will become constricted, so the blood flow will become poorer, fatigue substances will build up, and tiredness will not be eliminated or tiredness will increase.
Further, in the related art, the seat is vibrated only when the seated person turns an on/off switch of the vibration unit on. For example, even if the seated person becomes tired by sitting and driving etc. for a long time, if the seated person does not notice this or does not turn the switch on even if noticing it, the vibration of the vibration unit will not be utilized for reducing tiredness or suppressing an increase in the tiredness.
Still further, according to the vehicle air-conditioner of the related art, the detection signal of a pressure sensor includes a noise component due to bodily movement of the driver itself or bodily movement of the driver occurring along with driving of the vehicle in addition to the pulse wave component of the driver, so it is difficult for the tiredness judging means to accurately judge tiredness of the driver and it cannot judge tiredness with a high precision. Therefore, when the driver is not tired, the air-conditioning is controlled to reduce tiredness and the driver becomes numbed or when the driver is tired, the air-conditioning is controlled only as normal and the control of the air-conditioning for reducing tiredness does not work.